The shape and curvature of the blades of a boat propeller significantly influence the performance of the propeller. Such a blade is designed to hold the water on the working face of the blade to create a force against the water to create a forward thrust. The working surface of the blade is that surface working against the water. A greater force is produced by utilizing a greater portion of the working surface of the blade. However, prior art propellers, which are spoon or dish shaped and have progressive pitch, produce a great amount of resistance to water flow over the blade and, consequently, a terribly choppy ride. This effect is most profound during quick accelerations. Examples of propellers having completely or, in part, progressive pitch are disclosed in U.S. Pat. Nos. 1,030,047 to Ames and 2,754,919 to Blue.
The instant invention provides a significant improvement over the prior art by providing a propeller having a regressive pitch, the regressive pitch extending from the leading edge to the tail edge of each blade. The propeller having the regressive pitch produces a significant decrease in the resistance to water flowing over each of the blades of the propeller. Instead of restricting water flow, the blades having a regressive pitch cut through the water. Additionally , the blades are vented to control the water flow over the blades. The venting holds the water on the blades and directs the water flow. The maximum amount of the working surface of the blade is used, thereby increasing the efficiency of the propeller significantly. The instant invention results in increased acceleration with a concurrently significant decrease in agitation of the boat.